/**
 *    Copyright (C) 2018-present MongoDB, Inc.
 *
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the Server Side Public License, version 1,
 *    as published by MongoDB, Inc.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    Server Side Public License for more details.
 *
 *    You should have received a copy of the Server Side Public License
 *    along with this program. If not, see
 *    <http://www.mongodb.com/licensing/server-side-public-license>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the Server Side Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */


#include "mongo/s/query/exec/router_stage_skip.h"

#include "mongo/util/assert_util.h"

#include <utility>

#include <boost/move/utility_core.hpp>

#define MONGO_LOGV2_DEFAULT_COMPONENT ::mongo::logv2::LogComponent::kQuery


namespace mongo {

RouterStageSkip::RouterStageSkip(OperationContext* opCtx,
                                 std::unique_ptr<RouterExecStage> child,
                                 long long skip)
    : RouterExecStage(opCtx, std::move(child)), _skip(skip) {
    tassert(11052353, "Expected positive value for skip", skip > 0);
}

StatusWith<ClusterQueryResult> RouterStageSkip::next() {
    while (_skippedSoFar < _skip) {
        auto next = getChildStage()->next();
        if (!next.isOK()) {
            return next;
        }

        if (next.getValue().isEOF()) {
            return next;
        }

        ++_skippedSoFar;
    }

    return getChildStage()->next();
}

}  // namespace mongo
